Underground storage tank (UST) fueling sites, such as retail gas stations, include pipelines carrying a product such as gasoline from the storage tank to a product dispenser. Each pipeline typically includes a primary pipeline through which the product flows, and a secondary pipeline that surrounds the primary pipeline. The purpose of the secondary pipeline is to contain any fluid that may leak from a damaged primary pipeline, and prevent the fluid from contaminating the surrounding ground. As used herein, the primary pipeline and the secondary pipeline are referred collectively as the pipeline or the pipe.
A sump is also typically provided beneath the product dispenser to contain any fuel released from failed equipment and thereby prevent environmental contamination (e.g., ground water contamination) under and around the service station. Each of the primary pipelines extends through an aperture in the wall of the sump to a pipe fitting which connects the primary pipeline to the product dispenser. The aperture in the sump wall through which the pipeline penetrates must be sealed to prevent the accumulated fuel in the sump from leaking through the aperture in the sump wall and into the surrounding ground. Accordingly, penetration fittings are provided to form seals between the sumps and the associated pipelines to contain fuel leakage within the sumps.
Conventionally, flexible boots are used to seal between the pipeline and the sump because flexible boots can bend to accommodate pipelines that penetrate the sump wall at an oblique angle. However, conventional flexible boots are made of materials having a relatively low chemical resistance (e.g., rubber or plastic) that degrade quickly and prematurely fail in the harsh sump environment. When these conventional flexible boots fail and begin to leak, they are conventionally replaced with a split repair boot or fitting. However, these split repair boots are also conventionally made from a material having a relatively low chemical resistance (e.g., urethane based plastic) that tends to degrade and fail quickly in the sump environment. Additionally, because flexible boots must bend to accommodate pipes penetrating the sump wall at an oblique angle, the flexible boots are under constant stress which can lead to premature failure.
Other conventional penetration fittings may be made of a more durable material. However, such conventional fittings are generally rigid and must be installed during construction of the UST fueling site and the installation of the sumps. Installing these conventional fittings to retrofit an existing sump installation, rather than during construction of the fueling site, requires excavation of the surround soil, cutting the pipeline, and sliding the penetration fitting over the cut end of the pipeline. Accordingly, retrofitting an existing sump installation with these conventional rigid penetration fittings may be both cost and time prohibitive. Moreover, these rigid conventional fittings cannot accommodate pipes which penetrate the sump wall at an oblique angle.
Additionally, other conventional penetration fitting may use tapered wedges to accommodate pipes penetrating the sump at an oblique angle. However, such tapered wedges increase the overall profile or envelope of the fitting. The increased profile of the fitting may make the fitting unsuitable for use with certain sump and pipe configurations.